Electric switch and fuse box.



-fL. Ff KRIES.

ELECTRIC SWITCH AND FUSE Box.

APPLICATION FILED MAR. l2. 1910.

Patented May 1, 1917. 3 SHEETS-SHEET l L. F. KRIES. ELECTRIC SWITCH ANDFUSE BOX. APPLICATION FILED MAR.12. 1910.

11,224,880., Patented 111315711917.

3 SHEETS-SHEET 2 l Y* 1 w Q@ l Aww L. F. KRIES. ELECTRIC SWITCH AND FUSEBOX.

APPLICATION FILED MAE. I2. 1910. 1,224,880.

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vriiTEp sTATEs PATENT oEiEicE.l

LAWRENCE F. KRIES, OF BALTIMORE, MARYLAND, ASSIGNOR TO CHARLES MORGANMARSHALL, TRUSTEE. F BALTIMORE, MARYLAND.

ELECTRIC SWITCH AND FUSE BOX.

l To all 'whom it may concern Be it known that I, LAWRENCE F. Kaine, acitizen of the United States, residing at Baltimore city, in the Stateof Maryland, haveinvented certain' new and useful liuprovements inElectric Switch and Fuse Boxes, of which the following is aspecification.

My invention pertains to boxes or holders for electrical apparatus, andis designed to permit the opening thereof whenever necessary forinspection or renewal of the. apparatus, but to preclude the passage ofthe current to the apparatus while the box or holder is open, and toprevent the possible taking of current at such time from within thechamber. Though susceptible of use in various other relations or withother apparatus, the invention is primarily intended for, and isillustrated in connection with, a switch and fuse box for theintroduction of current from a service main into a room or buildingWhere the current is to be used.

Briey stated, the invention' consists in a novel construction andarrangement of parts,i prominent among which is a closure for the fusebox or apparatus-containing chamber, which closure is so connected withor related to a line switch inaccessibly mounted in a separatecompartment that the switch must be opened before, and remain openduring, the opening of the containing chamber.

' and combinations will lbe pointed out.

' of fuse boxes and the like.

.is capable of being freely opened to give i access to the fuse 0rfuses, with the conse-l Under prior constructions two plans havecommonly been adopted for the construction lha one, the box quence thatthere is considerable danger of inexperienced persons receiving a severeshock through the handling of live contacts, y

and there is. the possibility of robbing the supply company of itscurrent by carrying Aoff branches from the fuse holders or contacts.

To obviate'these objections it is now quite common to adopt the 'secondplan, which consists in providing the cover or closure of the box orcontaining'chamber with av lock,

the key of which is retained by an agent of the compa-ny supply current.This latter plan is objectionable, in that in case a fuse blows outor`is destroyed, or other apparatus is yput out of order, delay isoccasioned Specification of ,Letters Patent.

Various other features, details,v

distance from the base 2.

Patented May 1, 191'?.

in making repairs, owing to the necessity of sending for and awaitingthe arrival of the keeper of the key.

By my invention I avoid these several difficulties, give free and promptaccess tothe interior of the box or containing chamber, preclude a-llchance of accidental contact with live wires or conductors, and renderimpossible the vtaking of current from within the box or chamber while.said box is open. rllie details of construction may vary widely withinthe limits ,of my invention, convenient forms of the structure, whendesigned as -a fuse box.l being represented iii the accompanyingdrawings, in which Figure l is a longitudinal section of the completedevice on the line l-l of Fig. 3, showing the switch closed;

Fig. Q is similar to Fig. l but shows theI positions assumed by thevarious parts when the switch is open;

Fig. 3 is a longitudinal section on the line 3 3 of Fig. 2;

Fig. 4 is a transverse section on the line 1 -'4- of Fig. 3;

Fig. 5 is a perspective view of the locking` slide and switch;

Fig. 6 is a longitudinal section of a modified form of the deviceadapted to operation from the front;

Fig. 7 is a perspective view of the locking segment and switch of thestructure shown in Fig. 6; and

"Fig, 8 is a longitudinal section of a moditication in which themovements of a door actuate the switch.

Referring by numerals to the structure shown in Figs. l to 5 of thedrawings, l represents the casing or box that incloses the tlevice.rlhis may be of cast iron, pressed steel or any 'other suitablematerial, the principal requisites being that the box be tight andstrong. So far as possible the use of screws and other removablefastenings is avoided throughout the construction of the box to preventany tampering with its mechanism. Y

.A slate or other non-conducting base 2 such as is commonlyused forswitches and fuses is attached to the back of the box, to support andinsulate the electrical mechanism. A strongpartition 3 extends clearacross the box and down -to within a short This partition divides thebox into two chambers 4e and 5 which I shall call the fuse chamber andswitch chamber respectively, though it will be understood that otherapparatus than fuses might be inclosed therein. The partition 3 isinsulated from the connections carried by the base 2, by insulatingstrips Gextending beyond its edge and attached by screws 7 insulatedfrom. the switch chamber side.

lVhere the switch box is used to control the circuit entering abuildin-g, the connev tions from the street main will enter the box atS. ln such service a lead sheathed cable 9 is commonly used and aconvenient mode oil attaching such cables is to provide a conical nipple10 on the box, force the lead sheath 11 of the cable over this nippleand clamp it in place with a ring 12 held by bolts 13.=^ Any othersuitable method may of course be employed, the idea being merely toSecure a tight joint between the sheath and the box.

'llhe line or supply wires 141-, leading from the source of currentsupply, through cable il, enter the casing and their ends are connectedto the supply wire terminals 15, to which are secured Athe live switchcontacts 15 of a switch S. These terminals and u, switch contacts aresuitably secured to the base 2. lin the drawings, the invention is shownin connection with a three-wire system, :for illustration; but obviouslyit is adapted for any number of wires by simply varyingl the number ofswitch blades, contacts, tuses, etc.

llhe switch S is adapted, when closed, to electrically connect thesupply wires in the part 5 of the casing with the fuse terminals in thepart et, and when the switch is open, the electrical connection betweenthe supply wires and said fuse terminals is broken. The switch S ispreferably a knife switch having blades 16, pivoted to switch terminals17, and movable into and out oi engagement with the live switch contacts15. The switch terminals 17 are connec i," by conductors 13 to the fuseterminals 2u. llVhen the switch S is closed, the circuits are completedfrom the supply wires through the switch to thel conductors 13 and fuseterminals 20, thence through fuses 19 to the fuse terminals 20,connected to condimtors 21, which latter are suitably incloscd, as by ametallic conduit 22, and lead to the meter and house connections. Theconduit 22 may be connected to the box by a nipple 23 and sleeve 24, asshown.

rlhe ends oir the supply wires, the supply wire terminals, and theswitch contacts 15, all oi which parts are constantly alive, are in thepart 5 of the casing` and inaccessible ,from the part 4 thereof, byreason of the partition or barrier 3. As shown in Figs. 1 and 2, theswitch blades are alsov wholly within the part 5 and inaccessible fromthe part 4l. Access to the chamber or part 5.

switch chamber is available only to authorized employees of the electricpower company. Y

The switch, however, may be operated by anyone through the followingmechanism. The switch blades 16 are connected to move in unison by aninsulating bar 29 which is mounted at its ends on the arms 30 of bellcrank levers 31. The levers 31 turn on pivots 32 on the box 1, thepivots 32 being alined with the pivots 17n in the switch blades 1G.

The other arms 33 of the `bel/l crank levers 31 are slotted at 34 toengage the pins 35 which are carried by the slides 3G guided in slots37, in the partition 3 and an end wall ot case 1. The slides 36 areconnected by a handle 38 carried on a bolt 39, the slides, bolt andhandle constituting a bail'. Thus the switch is closed by the inwardmovement oi the slides and opened by the outward movement thereof. Theinward motion of the slides is limited by the cngagement of the lugs 40with the partition 3 (see lfig. l). The switch may be sealed open byremoving handle 33 and attaching it in the position indicated in dottedlines in ligs. 2 and 3 by passing bolt 39 through the holes 41 in slides36 and sealing it in `place with the lead seal 42 (Fig. 3), a hole 43being provided in bolt 39 for that purpose.

lt is often desirable, both on behalf of the power company and thecustomer, when a building is vacated, to be able to lock the switch iuopen position, so that no one but an authorized person can close it, andthis is accomplished in a simple manner by the means j ust described.

access to the fuse chamber 4i can be had only through the apertureclosed by door 4 1. This door is pivoted at 45 the pivots being somedistance from the edge oit' the doorso that as it is opened a heelportion 41.6 et the door swings into the chamber. W hen the slides 36are in any position but their outermost one the heel 4:6 is preventedfrom inward motion by the slides 36 so that the door cannot be opened..When however the slides are in their outermost position a cam recess 47in the slides comes immediately behind the heel 46 and permits theopening or' the door. of the slides will close the door, and the partsare so proportioned that the door will be completely closed and heldclosed prior to the initial closing ot the switch. While the fuseterminals are thus accessible when A ver sliofht inward motion the dooris open, for the purpose of removing or replacing fuses, the switch isalso open and the accessible conducting parts are dead, while the liveparts of the apparatus,

which include the supply wires, supply terminals and live switchcontacts, are inaccessible through said opening by reason of the barrier3.

The modification shown in Figs. 6 and 7 is identical inl principle, butis arranged for use where a box set flush in a wall is desired. Partsidentical with those already described are similarly numbered in thesefigures and further explanation is needless. ln the modified structurethe bell cranks 31 are of slightly different form, and the slides 36 areguided in guides 4S and pass through the front of the box.

The switch blades 1G are shown pivoted in line with the barrier 3f, andtheir hinged ends are thus partly accessible when the door 44 is open;but as the switch is always open when the door is open, and the door isalways closed before` the switch is closed, it is impossible to eitherreceive a shock or steal current from the .switch blades.

Cam segments 49 are carried by the bell cranks 31 and serve to engagethe heel 46 on the door 44 so that no c-am recesses appear in the slides36. The case 1 is provided with rearwardly projecting chambers 50 togive the necessary clearangy' f ln either of the struct/ure describedabove access may be had to the fuse chamber only after opening theswitch, and before the circuit can be again closed the door 44 musttightly close. lt is impossible tosteal current from the fuse terminalswithout actually breaking the boX as the current can bev turned on onlywhile the door is closed, and it closes too tightly tov permit wires tobe led around the edges.

As such fuses are customarily mounted between the street mains and themeter, this point is of the greatest importance.

Y ln the modification shown in Fig. 8 parts already described bearcorresponding numbers. rlhe bell crank lever 31 is similar .to thatLshown in Figs. -1 to 5, but the slot 34, slides 36 and parts carriedthereby, and the heel 46 on the door are omitted. y instead, the armsSBare connected by links 51 to inwardlyprojecting arms 52 on the door, theparts being so proportioned that a slight opening movement of the dooreffects the complete opening of' the switch. A flange 53 conforming tothe path of the edge of the door and projecting from the front of thebox prevents access thereto, until the switch is fully opened. Thisembodiment is not, however, as desirable as the others since it isdiflicult to secure a satisfactory opening of the switch on asufiiciently small movement of the door and also because the door mustremain open so long as the switch is open, whether access to the chamberis desired or not.

The construction shown in Fig. 8 is not specifically claimed in thepresent application, visional application, Serial No. 7 87 ,438, filedAugust 30, 1913, in which it is described and claimed.

lf for any reason desired, a glass window 54 may be placed in door 25 topermit a clear view of the switch, as illustrated in Figs. 6 and ,8.

llt is obvious that-other forms of electrical apparatus in addition toor in place of the fuses shown, might be inclosed in chamber 4, theessential idea of the invention being the combination of anapparatus-containing chamber and a switch in such a manner that theopening of the apparatus containing chamber becomes possible only whenthe `switch is open.. Additional features are the isolation orinaccessibility of all parts that Aremain alive when the switch is openand various structural details above set forth.

Obviously, various changes and modifica:

tions are possible without departing from the spirit and scope of theinvention. For

instance, instead of having the wires enter or leave the box ato-pposite ends, they may all be arranged at one end, or they may enterand leave at the sides, or in fact at any desired points, but should beled through the switch and fuses in the ordery or arrangement here setforth. lf the supply wires enter through the fuse chamber in passing tothe supply wire terminals in the switch chamber, they should of course,be protected against access in the fuse chamber, as otherwise currentcould be taken from them. l

Having thus described my invention, what l claim is l. rFhe combinationwith a casing having an opening, and ay door on the casing for closingsaid opening, of fuse terminals in one part of the casing, accessiblethrough said opening when the door is open, supplywire terminals andlive Switch contacts in another part of the casing, a barrier within thecasing preventing access through said Opening to said live terminals andswitch contacts, a movable switch-member within the casing forconnecting said switch contacts with said fuse terminals, and means"operatively related to the door and switch open and inaccessible whenthe door is-v closed, supply terminals and live switch contacts inanother part of the casing, a barrier switch members and for within thecasing preventing access to said supply terminals and switch contactswhen the door is open, movable switch members within the casing forconnecting said switch contacts with said fuse terminals, and anaccessible mechanism for actuating said simultaneously controlling thedoor, said mechanism comprising means for preventing the door from beingopened while said switch members are in closed position, and forpermitting the door to be opened after said members have been moved toopen position.

` 3. The combination with a casing having a door thereon, of fuseterminals in one part of the casing accessible when the door is open andinaccessible Whenthe door is closed, supply terminals and live switchcontacts in another part of the casing, inaccessible through saidopening, movable switch members for connectingsaid switch contacts withthe fuse terminalaand means operable from without the casing foractuating said members and door, said means acting to close and lock thedoor when said members are moved toward closed position and to releasethe door when said members are moved to open position.

..The combination with a casing having a door thereon, of 'fuseterminals in one part of the casing accessible when the door is open andinaccessible when the door is closed, supply terminals and live switchcontacts in another part of the casing, a barrier within the casingpreventing' access to said supply terminals and switch contactswhen thedoor is open, pivoted switch arms for connecting said switch contactswith the fuse terminals, and means operable from; without the casing forrocking the switch arms and acting to close and loch the door when saidarms are moved toward'closed position and to release the door when saidarms are moved from. closed position.

5. rlhe combination with a casing having a door hinged thereto, of fuseterminals in one part of the casing accessible when the door is open andinaccessible when the door is closed, supply terminals and live switchcontacts in another part of the casing, a barrier within the casinoqreventin access to said supply terminals and switch contacts when thedoor is open, pivotally mounted switch armswithin the casing forconnectmg said switch contacts with the fuse terminals, and meansoperable from without 'the casing for rocking the switch arms and'controlling the door, said means acting to lock the door when said armsare moved toward closed position to release the door when said arms aremoved from closed positionn 6. The combination with a terminals in onepart of said casing, supplywire terminals and a switch in another partswitch contacts in contacts with said fuse terminals,

casing, of fuse ating mechanism for the switch nect the latter terminalswith the fuse terminals, a door, hinged to the`casing, for permittingaccess to the fuse terminals, said i door having a projecting partadjacent its pivotal axis, a barrier within lsaid casing for preventingaccess to said supply-wire terminals and switch, and mechanism foractuating the switch and simultaneously controlling the door, saidmechanism being operable from without the casing and comprising-meansacting to engage said pro,- jecting part on the door and lock the doorwhen the switch is closed.

7. The combination with a casing having an opening, and a door, hingedto the casing, for nals within said casing accessible through saidopening when the door is open, supply wire terminals and live switchcontacts in another part of the casing, inaccessible through saidopening, movable switch memybers within lthe casing for connectinof'said fuse terminals with said switch contacts, and actuating mechanismfor the switch operable from without the casing, said mechanism and doorhaving' interlocking .parts acting to automatically loci: the door inclosed position when said mechanism is moved to close theswitch, theinterlocking part on the door being located adjacent its pivotal axis.

8, rlhe combination with an opening, and a door on the casing forclosing said opening, of fuse terminals in one part of the casingaccessible when the door is open and inaccessible when the door isclosed, supply-wire terminals and live another part of the casmg,inaccessible through said opening in all positions of the door, rockingswitch arms within the casing' for connecting said switch contacts withsaid fuse terminals, and mechanism` for operating said switch andsimultaneously controlling the door, said mechanism comprising a slidingmember projecting through one wall of the casing and having means forclosing and locking they door prior to the closure of the switch andunlocking the d oor subsequent to the lopening of the switch. l Thecombination with an opening, and a door on the casing lor closingsaidopening, of fuse terminals in one part of the casing accessible, whenthe door is open and inaccessible when the door is closed, supplywireterminals and live switch contacts in another part o'f the casing,inaccessible through said opening in all positions of the door, rockingswitch arms within the casing for connecting said switch and operanddoor comprising a pair of rods projecting through one wall ot the casingand a handle piece closing lsaid opening, fuse termi-- a casing havingvconnecting said rods outside the casing, said mechanism having means forclosing and locking the door prior to the closure of the switch andunlocking.. the door subsequent tothe opening of the switch.

10. The combination with a casing having an opening and a door on thecasing for closing said opening, of fuse terminals in one part' of thecasing accessible when the door is open and inaccessible when the dooris closed, supply-wire terminals and live switch contacts in anotherpart of the casing, a barrier within the casing preventing access tosaid supply terminals and switch contacts through said opening, movableswitch members within the casing adapted to ,connect said fuse terminalsand switch contacts, mechanism for operating said switch members and forsimultaneously controlling the door, said mechanism projecting -outsidethe casing and comprising means for locking the door when the switchmembers are in closed position and releasing the door when -the switchmembers have been moved to open position, and means for locking the saidoperating mechanism so as to hold said switch members in open position.

11. The combination with a casing having an opening and a door on thecasing for closing said opening, of fuse terminals in one Apart of thecasing accessible when the door is open and inaccessible when the dooris closed, supply-wire terminals and live switch contacts in anotherpart of the casing, a lbarrier within the casing preventing access tosaid supply terminals and switch contacts through said opening, movableswitch members within the casing adapted to conneet said fuse terminalsand switch contaets, mechanism for operating said switch members and forsimultaneously controlling the door, said mechanism comprising a bailhaving its arms projecting through the casing, said arms havingperforations adapted to receive a locking rod, outside the casing, whenthe switch members are in open posi-` tion, and said mechanism vhavingmeans for locking thel door when the switch members are in closedposition and releasing the door after said switch members have beenmoved to open position.

12. rEhe combination with a casing having an opening, and a door hingedto the casing for closing said opening, of fuse terminals in one part ofthe basing, accessible when the door is open and inaccessible when thedoei' is closed, supply-wire terminals and Alive switch contacts inanother part of the casing, inaccessible through said opening,

' pivoted switch memberswithin the casing adapted to connect said fuseterminals and switch contacts, mechanism for operating said switchmembers and simultaneously controlling the door, said mechanismprojecting outside the casing and comprising means for locking the doorwhen the switch members are in closed position and releasing the doorwhen the switch members have been movedA to open position, and means forlocking the said operating mechanism so as to hold said switch membersin open position.

ln testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

`lUAWltENCE F. KRIES. `Witnessesz WM. Gr. SPEED, HARRY B. Ross.

